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jase
21-06-2008, 02:23 PM
Need a couple dumbbells StrongmanMike?

Hi All,
Back to business after the recent CWAS posts. In an attempt to cater for different tastes, my latest efforts have leaded me down two paths of which I’m pleased to present:

M27 – Dumbbell nebula in true colour (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=154&fld_album_id=11) for the traditionalists.
True colour image is a Ha [Ha+R]GB composite totalling 4.7 hours (Ha:120mins;R:55mins;G:55mins;B55mi ns).

and...

M27 – Dumbbell nebula in mapped colour (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=153&fld_album_id=11) for the NB aficionado (Fred, Ric and others).

NB image is a SII:Ha:OIII (Hubble Palette) composite totalling 4.3 hours (SII:70mins;Ha:120mins;OIII:70mins)

About the target;
The Dumbbell nebula (M27) is a gaseous emission nebula residing in the constellation Vulpecula. Its name was derived from early astronomers who sighted it has having two distinctly shaped sides looking like a Dumbbell weight. The shape of the nebula is due to the central star expelling its layers as its core nuclear fuel supply diminishes. M27 resides 1,200 light years away.

Some words on the image (Usual bantering for those interested):

All NB data was acquired using Lightbuckets (http://www.lightbuckets.com) 24” RCOS (4876mm @ F/8) under the pristine dark skies of New Mexico. Attached to the business end of the scope is the Apogee Alta U42 CCD camera which is a great match for this instrument (NABG, back illuminated, high QE, good sampling, 100k well depth – enough said). The camera is deceptive – I would have thought it would bloom on the Ha filter on 600sec subs, but it didn’t. It may with a different field i.e. a bright star present but around the dumbbell this wasn’t an issue. Rather impressive to capture the outer shell in only 120mins of Ha data. I guess that's what sensitivity coupled with 600mm aperture will provide. This optical system will devour any galaxy in its sight. Big drool factor.

OK, with that rant out the way on to the more interesting side of imaging, the processing. Ha data was acquired on the Dumbbell as it crossed the meridian so was of great quality. No meridian flips - it’s an eq. fork. For the purpose of this exercise, I’m only going to explain the narrowband processing. If you want info on how I conducted the processing on the true colour data, pls PM me – it was similar to the M83 image where I used RGB data from a different focal length system to colour the high resolution luminance – a bit of star colour matching required – not fun.. Anyway, subs calibrated in MaximDL, registered in Registar and then combined using Sigma Reject back in MaximDL. Ha, SII and OIII combined files passed through 2 iterations of LR deconvolution. Proceeded to perform an initial stretch in DDP. The stretch wasn’t aggressive i.e. to fill the full bit space, but mild. This is to make the clipping masks a little easier to deal with in the next phase. I thought I’d try the Hubble palette on this target even though I knew I wouldn’t shine towards green Ha nebulosity. I’ve seen a few other renditions such as CFHT (Canada-France-Hawaii Telescope) aka HOS and also simple Ha and OIII (bi-colour mapping). So SII:Ha:OIII were mapped to R:G:B respectively. I introduced each layer into PS and began creating clipping masks. I used the same process in which Dr. Travis Rector utilises to map some of the Hubble images. I’m not going to cover the specific clipping mask process here. You’ll find a white paper by Dr. Rector under the resources section of my site titled “Creation of Presentation-Quality Astronomical images”. A worthy read if you’re looking to step up your imaging output. Further stretch images using curves (as clipping masks). Image was then flattened after clipping masks looked close to bring out each emission line. The dumbbell does not contain much SII data. Looking at the subs, the signal is rather weak. Ha and OIII (particularly OIII – raw data sample of OIII (http://www.cosmicphotos.com/reprocessed/Jase-M27-OIII.jpg)) are very strong. The SII data is shown as a yellow hue as it mixes with the green Ha data. No mixing of Ha into the other channels to provide resolution – nothing but clean emission lines here. The background noise in the NB image is due to stretching the SII rather hard – classic example of a weak signal (I should have masked it). May look at doing a Ha:OIII rendition in the future. Strangely, I’m starting to warm to the SHO palette despite the green Ha data!

Quick note on the RGB version, the RGB was acquired sometime ago (actually last year) using a TOA-150/ST10XME. I did have intentions to use the 24” RC to collect the RGB data, but with full moon around at the moment, I thought I’d try my hand a mixing different focal length data (yet again). I think some luminance data on this target would bring back the stars in a more pleasing manner. The Ha data stars were very tight and round which didn’t match well with the lower res RGB data. (Check out the star trio at top left – prime resolution as you would expect from this aperture).

Before I close, I’d like to say a few words about the Lightbuckets operation. Steve and Alvin have been exceptional to deal with during the data acquisition process. They are imagers at heart and take great pride in delivering the best possible data to you. While they are just warming up, they’ve completed an amazing array of features to make it easier to image remotely. From configuring a “set and forget” fully automated acquisition session through to intricate details of a flats library for any potential imaging angle you choose, thus providing flat field accuracy. Incredible work and dedication. Again, like GRAS, I’m not associated with their operations (this is based on personal experience), I’m simply a user of their services.

Anyway, hope you enjoy them.
Hmmm (5m F/L)…Nothing like a bit of deep space in your face! YEAH!:D

Cheers

leon
21-06-2008, 02:45 PM
:eyepop:Wow Jase, an other master piece as expected, although both are excellent, I do prefer the first, but that is MHO only, awesome shooting ;)

Leon :thumbsup:

strongmanmike
21-06-2008, 02:49 PM
Hmm?..lets see? That star would have been at least as heavy as our Sun soooooo thats 10 to the power of 30 kg or so of expploded gasses plus a white dwarf...?...yeh! EASY! :D

Your posts are becoming bloody books Jase :lol:

Very nice dumbell image and yes I agree, to reveal this in such a short exposure is pretty cool...A dumbell image without the faint outer ejecta is becoming a pretty ordinary image these days :scared:

I want a high QE/well depth CCD now :sadeyes:

MIke

skeltz
21-06-2008, 03:27 PM
I think it looks like my brain,about to explode after trying to understand all these processing techniques::face:
But seriously ,they look **** hot and i would say i like the real colour one best.:jump:
At least with remote imaging you can get clear skys somewhere:)

renormalised
21-06-2008, 03:52 PM
Great piccies, Jase. Both of them:)

I like both traditional and mapped colour data, they both have their place and can look as good as one another. If done correctly, they can both bring out a lot of good detail that's scientifically useful when studying nebula etc.

Bassnut
21-06-2008, 03:57 PM
Totally awesome Jase, the nebula extension and core detail is exceptional.

On zooming in (im allowed to, given the gear list :D) there seems to be a bit of colour noise in the background, but that could be the upscaled RGB data you added, and given the object is pretty dim, even 4hrs odd is not a lot of time.

Interestingly star halos are stronger on the true colour image, usually the NB suffers that problem more, but you used Ha on the true colour image too, so that might explain that.

When the colour data is not the best, I find using Ha as a lumanence channel in NB (as in Ha;sII;Ha;OIII) allows detail boost, but of course colour is then somewhat washed out and the colour channels need lum added (as you seem to be good at).

All in all, a wonderfull effort Jase, its the 1st lightbuckets customer image Ive seen, ive been waiting for that, and its impressive I must say.

We live in interesting times ;).

iceman
21-06-2008, 04:15 PM
Wow, now that took me by surprise. I don't think i've seen anything quite like it from the ground before. A 24" scope, now that is something.

Simply amazing, Jase.

Remote imaging really delivers the goods, and at an infinitely small percentage of what it would cost to acquire that gear yourself.

Tamtarn
21-06-2008, 06:29 PM
A simply stunning image Jase. Never seen such detail in M27 before the outer detail is awesome. Thanks for sharing such a fine image.
24" RCOS - 4876mm F/L - 4.7hrs :eyepop:

We'll have to give it a go with the Skywatcher :lol: :lol: :lol:

Alchemy
21-06-2008, 08:10 PM
everyone else seems to like the normal one, i actually prefer the mapped version.

the detail in the Ha emision is lovely within the nebula on both images... i presume its the same data.

i find the halos around the stars on the RGB one distracting to me,( i did note you could improve it with more data in your disertion at the start).
given your processing skills i think you could improve on the sky background noise too.

jase
21-06-2008, 08:34 PM
Thanks for your comments Leon. :)Yes, a true colour image is always a crowd pleaser. Narrowband takes some getting use to. I enjoy working with narrowband has it allows for more creative expression.



Cheers Mike. Reading the blurb is optional mate. ;) One day, I’ll shock you by just posting a link to the image. Agree, you know when you’ve done this target justice when you see the fainter features/ejecta. I hear you regarding high QE/well depth. The Alta U42 has a peak QE of >90% @ 550nm. Leaves the KAI-11002 for dead. Time for an upgrade?:D



Thanks Rob.:) Providing you know the principles of processing, that’s all that counts. I have a few routines I use. I’m still learning the ropes. Yes, the joys of remote imaging. Though its not always clear, but you do increase your chances of acquiring data.



Thanks Renormalised. I still feel NB imaging is rather artistic over scientific. You still strive for something aesthetic. Takes a while warm to pink stars for example. I don’t think the SHO palette is ideal for this target, hence may rework the data another time.:)



Hey Fred, thanks for your comments. :) Yes, the background colour noise is the upscaled RGB. What do you expect when trying to match 1050mm data to 4876mm! A much better option was to acquire RGB on the 24”, but with the moon still bright, I thought I’d use some data previously acquired. Again the star halos are due to the upscaled RGB. As mentioned in the original post, I need luminance data to make the stars look normal. The Ha data stars are very tight/small. I did think about blending the Ha data into other emission lines i.e. make the blue channel a blended combination of OIII + .2 Ha to simulate H-beta. However, I decided on the cleanest emission lines possible. May rework the data in due time. Thanks again.



Cheers Mike. :) Yes, the 24” RCOS @ Lightbuckets is a killer set up. You’re right, remote imaging continues to mature. I feel many people are still somewhat overwhelmed by the prospects of taking an image remotely. It’s actually no different to acquiring data on your own equipment; it still needs to be processed in a similar manner. A great image is not handed to you on a silver platter, that’s for sure. You still need to work for it.



Thanks Barb and David. :) Pleased you liked it. Its good to see a comparison of both true and mapped colour I guess. I was originally only going to post the mapped colour.



Cheers Clive. :D Each to their own regarding true or mapped colour preferences. I don’t think SHO palette is the best for this target. Yes, the halos and background noise are from the upscaled RGB. It is complex to match the different FL data, especially if it’s mediocre (which was the case with the RGB). I’ll be looking to take RGB from the 24” assuming I don’t lose interest on this target. Thanks again.

Ric
21-06-2008, 10:27 PM
Woo Hoo Jase, two superb images I love them both with a slight tendency towards the colour mapped image, of course. :whistle:

I have never seen that much detail in any other image of M27 and I do enjoy reading your write ups and processing details.

As you mentioned colour mapping can be a great artistic release at times and I will be interested to see your variations on the SHO palette.

Cheers:)

jase
21-06-2008, 11:12 PM
Cheers Ric. :) Pleased you liked them. Indeed, I do intend to perform some variations to the NB palette. I suspect I'll go with a bi-colour composite - just Ha and OIII for this target assuming I can get the stars to look ok. Never easy. Thanks again.:thumbsup:

renormalised
22-06-2008, 12:16 AM
Thing is, Jase, with SHO colour mapping is that, when done well, you're tracing the distribution of HII (as Ha), SII and OIII in the object you're looking at. That way, you can tell the chemical evolution of the nebula plus any stars/remnants which maybe linked to that nebula. Yes, they are artistic, but I wouldn't expect nature to be anything otherwise. NB pics just bring that out...and so do traditional RGB when done well.

zipdrive
22-06-2008, 04:17 AM
wow! fantastic work jase.

Robert_T
22-06-2008, 06:55 AM
Hey Jase, what a fabulous insight into this nebula...my favourite is the mapped colour, looks like a giant inter-steller orchid bursting into bloom:thumbsup:

dcalleja
22-06-2008, 03:45 PM
Jase
Amazing work - I never knew PN's could have such huge extensions like that - It almost doesn't look like the same target.

I prefer the true colour version - but thats just me

Garyh
22-06-2008, 04:07 PM
Wow factor plus some alright!
Love that true color rendition Jase!
Don`t think I have ever seen the shell quiet like that before!
Might have to use that as some wallpaper!
cheers Gary

seeker372011
22-06-2008, 06:24 PM
wow.

I vote with those who seem to prefer the RGB version...just so much detail.

with these deep images someone is going to have to rename the object ..hardly just a dumbell or an apple core anymore
Narayan

gregbradley
22-06-2008, 09:06 PM
Amazing RGB image Jase. One of the very best I have seen of this object.

I for one like the blurb on the processing details as I find Photoshop and image processing is such a diverse and deep subject I like to find out more about it as I see the images I like. So thanks for the data.

Greg.

jase
22-06-2008, 10:25 PM
I hear you Renormalised. Though I think the SHO mapping doesn’t work well for every target…as is the case in this example. HOS or Bi colour appears to be the way to go for the dumbbell. Stay tuned, have started reworking the NB data set to come up with a Ha, OIII version. Thanks for your comments.:)


Thanks Dave. Pleased you liked them.:D



Cheers Rob. Never thought of it as an interstellar flower, but the analogy works!:)



Thanks Dan. :) The nebulous shock waves certainly add an extra dimension. I pushed the data rather hard to get the extension out with only 600s subs. I hope to add 2hrs of Ha data using 900s to see what that will bring to the image.



Cheers Gary. I’ve found it interesting to gauge the forum’s reaction between the true colour and narrowband. I did this before with IC1848 in true colour (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=117&fld_album_id=11) and mapped colour (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=119&fld_album_id=11). Hold off on the wallpaper, I hope to have a better rendition coming.:D


Thanks Narayan. Typically, people associate going deep with mega data. However, I feel this image goes to show that you don’t need mega data when you’ve got aperture and more importantly sensitivity. The Alta U42 is an excellent camera. It certainly not large format, but comes with some breath taking stats and price - http://www.bigbangastro.com/apogeeu42ccd2048x2048135midbandcame ra-p-2812.html
The guys at Lightbuckets certainly have a remarkable set up.



Thanks Greg. Pleased you don’t mind reading up on some of the techniques of used. More than happy to share the information/knowledge to benefit others.

========

Thanks again to all those who have made comment. Appreciate the feedback and kind words.:thumbsup:

seeker372011
23-06-2008, 06:56 PM
U42 camera on sale for US $38,500 only:jawdrop:..this is where remote imaging comes into its own..who could justify spending so much on just a camera-especialy given the three nights a year that it seems to be clear

jase
23-06-2008, 07:20 PM
:lol: ...and add another US$15k for a Grade 0 back illuminated chip with no defects. Seriously though, you're right...this is where rental scopes come into their own league. Even if I came into serious money to buy my own 24" RC, I wouldn't do it...Why? I simply don't have the environmental conditions to fully utilise such equipment. It would be a waste of time and money. Sure, if you've got a block of land up high up in the blue mountains where seeing is great, go for it. When you crunch the figures, its more economical to buy time on high end gear than purchase it yourself (especially when considering weather etc). Depends on how keen you are...

Bassnut
23-06-2008, 07:28 PM
$38,500?, cheap rubbish, spend $200,000 and then it gets interesting (and thats for a regular retail buy now astrocam), cant find the link, ill look more. BTW It has a cloud filter :).

jase
23-06-2008, 08:23 PM
Jealousy will get you nowhere Fred. ;) I know you want one for your rental rig. The 200k chip you are referring to is probably the Fairchild imaging chip...Its an 85mp monster - http://www.fairchildimaging.com/products/fpa/ccd/area/ccd_595.htm
I could count on one hand the type of scopes suitable for such a large chip, I'm afraid your 10" RC isn't one of them. Though the FSQ with its 88mm image circle would handle it well.:D

RB
23-06-2008, 08:55 PM
How stunning is that !!!!
Reminds me of an opal gemstone.

Superb work Jase, I love both versions.
I signed up to Lightbuckets too when you first mentioned it in another thread.
Hopefully I'll get around to trying it out at some stage.
I think it's a great idea and well worth giving it a go.

Bassnut
23-06-2008, 09:04 PM
Thats the one. Jase, itll fit my new comming_soon 32' RC no sweat (if it works on a G11).

Dietmar
26-06-2008, 03:55 AM
incredible image, Jase!
wonderful!
I like the true colors most!

richardo
26-06-2008, 05:08 PM
Hi Jase,
glad I caught this one.... aaahhh, two:P

I like them both.
Pin point stars all around, good teal colour to the standard and good use of the Ha data to accentuated the details within and to the outer shell.
Very nicely incorporated.

I do like mapped colour if only for something completely different.
My favourite palette combo is Ha=R: SII=G: OIII=B..
But then again it depends on what ones eye finds appealing.

Good stuff!!

Rich

renormalised
26-06-2008, 05:44 PM
Nope..damn the money. If I ever win enough in the Lotto, it'll be a 40" OGS RC setup with that Fairchild chip in a top of the line CCD rig. Or maybe a similar sized RCOS rig running at f/5 with the same CCD camera.

Although, I'd settle for an Apogee:D

And you can all use it, if you ask nicely:P:D:D

And I have the time to lend you:P:D

jase
26-06-2008, 08:38 PM
Thanks Andrew. :) I think the true colour and mapped scream for more data. I've been looking that high res images of these over the past few day and have some ideas on pushing them further (improved colour saturation etc). I've also managed to collect close to 2 hours more of Ha data using 900s subs. This should bring out the faint ejecta without introducing noise (I hope). Indeed, you should give remote imaging a shot. I keep telling people that they can acquire high resolution luminance from these rental scopes and combine it with your own RGB data. Endless options when it comes to imaging. Thanks again.



Thanks Dietz. Pleased you like them.:D The true colour appears to be the favourite (or so my site statistics indicate). Needs luminance to counteract the tight stars in the Ha data. It can be improved that's for sure.



Cheers Rich. Yes pinpoint stars:D, but I would expect nothing else with this gear. The RCOS pro series mounts deliver the goods. Quoted from the lightbuckets site;

"We’ve elected to use Ray Gralak’s PEMPro software (www.ccdware.com) to train the PEC. At this point there does not appear to be much PE but for a complete install we need to check it out. The data are in arc-seconds. After 12 complete turns of the worm (1608 seconds of data), the data looks mostly like noise to me, very little PE. We know that all worm gear systems have to have periodic error so using PEMPro here is the bottom line on raw periodic error for the RCOS Pro Series Fork Mount: Peak to peak PE of 2.6 arc-seconds or RMS 0.781 arc-seconds. This is the kind of raw PE we would expect on a very much larger telescope - like the Keck!!!
After training of the PEC in the Bisque TCS-4000 controller, the PE truly is in the noise. I have never seen a mount so free of periodic error. The figures from PEMPro analysis are peak to peak PE of 0.79 arc-seconds, RMS 0.22 arc-seconds of PE. The proof is in the imaging."
http://www.lightbuckets.com/newsarticle/5/rc-optical-systems-24-ritchey-chretien-review/
Quality with a capital Q.

Yes, I've considered a HSO palette, may try it on this target. Will be interesting as the OIII is remarkably strong. Thanks again for you comments.



Well someone has bought a whopping big scope as the cloud gods are in disagreement. Its been cloudy/storms in Rodeo and Mayhill in NM (US) and also Pingelly in WA (AU) that last few nights. So I haven't been able to set up a session of either the 24", 20" or 14.5" RC's. Hope it clears so I can complete the mission (or start another:D).

=====
Thanks again for all your comments.:)

jase
01-07-2008, 11:12 PM
I don't particularly like rekindling old threads, but considering this is on-topic I'll provide an update.

I've recently reprocessed the HaRGB image of the Dumbbell Nebula utilising 267mins of Ha data (7x900s, 12x600s and 6x480s subs). This didn't do much to improve detail, but reduced noise. In addition, I worked double time on the RGB data in attempt to remove the halos introduced due to the upscaled data. I first combined the RGB data to make a synthetic lum and coupled this with the original RGB. Down scaled the Ha to match the LRGB, then upscaled the new "super" RGB (technically HALRGB) before using the data to colour the Ha. As the Ha data star were tight and small, I simply integrated them using lighten mode. Falling short of collecting RGB data on the 24" RCOS (which was planned but bad weather there has seen no imaging time) this will need to do for now(as I can still see room for improvement). I hope the halos are now to your satisfaction Clive. Happy to hear other constructive feedback.:)

You can see the "final" result clicking on the link below or on the original link posted;
HaRGB Dumbbell Nebula Revised (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=154&fld_album_id=11)

Focused on getting the HaRGB image in line. I was unable to revise the NB version of the image in time before I was approached - http://gallery.rcopticalsystems.com/gallery/m27mapcolor.html
This will have to suffice, however I do have a bi colour NB image (Ha:OIII) in the mix, but not completed - leaving that for cloud riddled nights... in which we appear to be having a lot of lately I should add.:(

Finally (off topic), for those that expressed interest to see an un-cropped (100% 1:1 scale) version of NGC6357 in my previous CWAS post - Here it is (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=155&fld_album_id=11) for your viewing pleasure. ...and for the record, purists who may have got a little upset by me vertically flipping and 180' rotating the wide field image for aesthetic reasons will now be pleased that I have restored equilibrium as shown here (http://www.cosmicphotos.com/gallery/image.php?fld_image_id=108&fld_album_id=11).:D

Cheers

monoxide
01-07-2008, 11:36 PM
veeeery nice!
dont know how i missed this one...
it really seems to have a 3D look to it.
plenty of detail in there too, i've become a big fan of these long focal length PN images.

renormalised
01-07-2008, 11:44 PM
That is nice, Jase. A great piccie, with lots of detail in M27's outer shell:)

Excellent:):)

RB
03-07-2008, 10:18 AM
Fantastic work Jase, I just love viewing the large versions.
It feels like I'm floating out in space and can just reach out and touch the nebulosity.

Thanks for sharing mate.

:) :thumbsup:

iceman
03-07-2008, 10:46 AM
Wow that's quite stunning. Excellent imaging.

sjastro
03-07-2008, 04:24 PM
A 24" RC!!

An excellent image Jase.
A convincing argument for remote imaging.

Regards

Steven

Bassnut
03-07-2008, 05:48 PM
Wow Jase excellent, (well, it would be), nice getting on the RCOS site, top work, (umm, does that mean yr famous now, can we still talk to you?)

strongmanmike
03-07-2008, 11:18 PM
Jase

Ok...<snip>...bah! :rolleyes:

This Dumbell image is really great and I enjoyed it, thanks....:cool2:
See you in Parks for that beer :cheers: ...or two, or three...:drink::drink::drink:....le ts see if we can get David pissed :evil:

Mike